This invention relates to connectors of the zero insertion force type for receiving and connecting an integrated circuit package with staggered leads to a printed circuit board or the like.
There are number of prior art zero insertion force type connectors for integrated circuit packages such as the patent to Cherian et al U.S. Pat. No. 4,080,032 granted Mar. 21, 1978 and the patents cited as prior art therein.
The connector of the Cherian et al patent operates by opening its normally closed spring contacts, on package lead engaging members, by a camming action and upon deactivation of this camming action, allowing the spring force of these contact members to close onto the leads of the package. Thus, electrical contact between the package leads and the connector leads depends upon the spring action of the connector leads. It can be appreciated that any such electrical connection is dependent upon the springs retaining their bias and any loss of this bias will result in a poor electrical connection due to the poor engagement between the package leads and the connector leads.
Too, with the emphasis today upon increasing the number of functions per chip and decreasing the size of the package, the use of staggered leads on a package is becoming increasingly popular since it allows more leads per package of a given size. The connector of the Cherian et al patent does not accept a staggered lead package.
This invention, however, discloses how a connector having a cam actuated spring device can accommodate staggered package leads and, being the reverse of the prior art, how the camming action asserts a positive mechanical force to create the electrical connection between the package leads and the connector leads instead of relying on any spring bias to make such a connection.